Apparatus for extinguishing fires



Oct. 5, 1948. H. v WILLIAMSON v APPARATUS FOR EXTINGUISHING FIRES 2Shegts-$heet 1 mRNEY Filed Aug. 17, 1945 Oct. 5, 1948. H. v. WILLIAMSON2,450,537

APPARATUS FOR EXTINGUISHING FIRES Filed Aug. 17, 1945 2 shee s-sham 2INVENTOR.

Patented Oct. 1948 meas'rus ron ex'rmomsnmc mas Hiidlng V. Williamson.Chicago. IlL, auignor to Cardox Corporation, Chicago, 111.. acorporation of Illinois Application August 1'7, 1945, Serial No. 611,009

11 Claims.

This invention relates to apparatus for extinguishing fires, and dealsmore particularly with inerting the atmosphere surrounding the fires toeffect such extinguishments.

This use of liquid carbon dioxide to put out fires has had recent widespread development. The equipment includes a container for the carbondioxide and a conduit extending from this container to the place of use.tical to store the liquid carbon dioxide under refrigerated conditionsbecause of the correspondingly reduced vapor pressure. This makes itpossible to utilize containers having walls.

When discharging liquid'carbon dioxide from a nozzle to atmosphericpressure, the carbon dioxide is discharged in the form of carbon dioxidesnow and vapor, the temperature of which'is approximately -i F. Thisextreme cold causes water vapor to be condensed from the surroundingand'entrained air. This condensed water vapor appears in the form of adense fog of water ice particles and water droplets, which reducevisibility to nearly zero. It the discharge takes place outdoors train adirect application type nozzle, the fog produced, although it reducesvisibility, is not too much of a handicap since it readily disperses. Ifthe discharge takes place indoors from a total flooding nozzle, the fogdoes not disperse readily and visibility remains reduced. If thedischarge takes place as the result of the automatic or manual operationof a fixed fire extinguishing system with the usual alarm.

period preceding the discharge, the lack of visibility is not toodetrimental although better visi- It is most pracrelatively thin bilitywould be advantageous. However, if the discharge is from a playpipe ornozzle from a mobile fire fighting, apparatus, the lack of visibility iscritical.

For instance, when a mobile fire fighting unit is used to totally flooda room in a building with carbon dioxide in order to extinguish a flre,the exact location of the fire is not usually known and whether or notthere are persons in the room is also not usually known. The visibilityis usually initially bad, due to the smoke and other fumes, from thefire and ii the room is flooded with carbon dioxide from the usualdischarge, ,the resulting low visibility makes it nearly impossible tosee the location oi the fire, possible asphyxiated persons, and otherobjects.

The apparatus of this invention has been developed in order to reducethe above fogging difl'iculties and to get greater inerting benefitsfrom a given amount of carbon dioxide. i i.

When carbon dioxide is discharged in the usual way from a storage tankdirectly to a place to be inerted, the resultant carbon dioxide snow isnot effective in helping to create a flre extinguishing atmosphere untilafter it sublimes. It is important, therefore, that this snow beconverted to vapor as soon as possible, and that all or the carbondioxide vapor be heated so'that it occupies a greater volume, that is,is less dense, and will inert more space.

It is an object of the invention to elevate the temperature of thecarbon dioxide being delivered through a conduit from a container. sothat the carbon dioxide discharging from the open end of the conduitwill be at such a high temperature that it will not lower thetemperature of the surrounding atmosphere below its dew point. Inaccordance with this feature of the invention, a heater is provided inthe conduit line to elevate the temperature of the flowing carbondioxide.

The heating of the carbon dioxide before it is discharged from thedelivery conduit has the important effect of making sure that it isfully vaporized. It therefore occupies a greater volume in the space tobe inerted and is more eflective in extinguishing the fire.

As a further feature of the invention, the flowing carbon dioxide iscaused by a jet action to draw into the conduit, hot combustion gases tomore rapidly increase the temperature of the flowing carbon dioxide.This is of additional benefit because the ,inerting effect of the carbondioxide is supplemented by the products of com bustion since they givean increased volume and, hence, ability to inert a greater space.

Another feature of the invention is the provision of means for removingfrom the combustion gases the moisture therein as a product ofcombustion. This removal of this moisture, which would otherwise enterthe space to beinerted, is important to maintain a low dew point in thespace to be inerted.

Another feature of the invention involves the use of the flowing carbondioxide to create a suction which will draw a fuel mixture into acombustion space so that heat will be generated for elevating thetemperature of the flowing carbon dioxide.

A still further feature of the invention involves the use of athermostat to control the delivery of combustible fuel which is used toheat the flowing carbon dioxide.

Other features oi the invention will appear from the followingdescription when considered in connection with the accompanyingdrawings.

tion

Figure 2 is a vertical section through the heater of the invention,

Figure 8 is a vertical section through a modified heater contemplated bythe invention, and

Figure 4 is a vertical section through a different type of fuel mixerwhich may be utilized in practicing the invention.

Referring mat to Figure 1,-this shows at 8 a container for the liquidcarbon dioxide. As is here shown, this containeris within a truck I formobile purposes, but the container 8 may as well be stationarilymounted. Associated with the container 8 may be a refrigeratingapparatus to maintain the carbon dioxide at a low temperature and at acorresponding vapor pressure, but the invention contemplates thepossibility of using carbon dioxide from a container which is notrefrigerated. The carbon dioxide is delivered to the place where it isto be used through a conduit 8 having a communication with the interiorof the container 8. A valve 8 in the conduit 8 controls the delivery ofcarbon dioxide therethrough.

In the drawings, the carbon dioxide is shown delivered to the interiorof a room- 9' within a building ill. The discharge end of the conduit 8extends through the window I I so that the escaping carbon dioxide willpass into the room and inert the atmosphere therein. As here shown, thedischarge end of conduit 8 is close to the floor and this has theadvantage of delivering the carbon dioxide upon the floor so that itwill rise and displace the smoke upwardly. This will resuit in greatervisibility near the floor and will also inert the atmosphere upon thefloor where the flre may be. However, in some cases, it may be desirableto direct the conduit 8 toward some other location, as the ceiling, ifit is desired that better visibility be attained there.

As has been explained, if this carbon dioxide which is escaping into theroom is delivered directly from the container 8 as has heretofore beenthe general practice, it will be so cold that it will lower thetemperature of the air within the room below its dew point and theresulting condensed moisture from the air will create a fog. This fogmay be so thick that it will be impossible for the operator to directthe escaping stream of carbon dioxide to the desired point, and moreoverit may portion thereof. Within the heater II the conduit is broken andthe ends are shaped to form an aspirator Jet. This includes theformation of a nozzle l8 at the end of the conduit leading from thecontainer 8 and the formation of a widened Venturi portion 20 at the endof the conduit leading to the discharge end. Inasmuch as there will be amarked expansion of the carbon dioxide ai'ter it escapes from the nozzlel8, it is preferable that the portion of the conduit 8 between theheater i8 and the discharge end of the conduit be of larger diameter.

When the valve 8 is turned on, the carbon dioxide directed through thenozzle l8 will have an aspirator effect within the Venturi 20 towithdraw the contents from the space within the heater. As a feature ofthe invention, combustible fuel is burned within this space and thecombustion gases are drawn into the Venturi 20 to mix with the carbondioxide vapors. The heat from these combustion gases raises thetemperature of the carbon dioxide so that when the vapors escape fromthe open end of the conduit 8 beyond the heater i5, they are at asufficiently high temperature that they will not lower the temperatureof the air .within the room 8 below the dew point. As a consequence,there will be no fog formed with the room 8 which will obstructvisibility. Moreover, the intermingling with these hot combustion gaseswill make sure that all the carbon dioxide is vaporized.

To supply fuel to the interior of the heater II, a duct 2| extendstherein through the bottom of the heater. At the upper end of this duct2| is a cap 22 spaced from the end of the duct and it is of concaveunder formation to direct the fuel downwardly. This downwardly directedfuel impinges upon a ceramic block 23 supported on the duct 2i andhaving a circular groove 24 therein. This groove serves to redirect theburning fuel and gases upwardly into the combustion space.

To ignite this fuel, any suitable means may be employed, but as hereshown, this may be accomplished by forming a port 25 through the sidewall of the heater through which a match may be inserted. This matchpreferably should be made be impossible for a searcher to find personswho i may have become asphyxi-ated within the room.

The gas delivered from the open end of conduit 8 may be raised to such ahigh temperature that it will not lower the air temperature below thedew point, by means of a heater, generally indicated at ll. As is shownin detail in Figure 2, the heater I! includes an outer shell i8 which,preferably, will be of metal. Within shell i8 are layers ll ofinsulating material and innermost thereof is a lining l8 preferably of aceramic material. The shell i8 is preferably of cylindrical shape incross section and has a flat bottom and a dome-shaped top, but it is byno means required that the heater have this particular formation.

As is shown in Figure 2, the conduit 8 passes through the heater ll,preferably, at the upper of a burning material, similar to that insparklers, so that it will not be blown out by the strong draft throughthe burner. The match preferably should have a handle part which willplug hole 28 to prevent entrance of air which might blow out the matchor dilute the fuel mixture within the burner.-

To the lower end of the duct 2| is affixed a charge forming device whichis here shown to be a carburetor 28. This includes a float chamber 21which receives liquid fuel from a receptacle 28 carried by the heater I8in any suitable manner. A float 28 within the chamber 21 maintains aconstant liquid level within this chamber.

The carburetor 26 also includes a duct 3| attached at its upper portionto the lower part of duct 2!, and the lower portion of duct 8! has anextension 82 through which air may-be delivered tothe duct 3|. A Jet 38extends from the float chamber 21 into the ductil to deliver the liquidfuel into admixture with the air flowing upwardit? through the duct 3|.

The suction eflect created by the nozzle l8 and Venturi 20 draws airinto the inlet 82 and upwardly through the ducts 8i and 2| and drawswith it liquid fuel from the jet 88. The combustible mixture which is soformed burns within the combustion space within the heater l8 and, ashas been stated, the combustion gases which are so formed are drawn intothe Venturi 20 to mix with the carbon dioxide vapor and elevate itstemperature. In addition, the high temperature within the combustionspace heats the nozzle l9 andVenturi 20 so that the carbon dioxide vaporis heated by conduction through these walls.

A valve 36. here shown to be of the butterfly type, is located in theduct H to regulate the flow of the combustible mixture into thecombustion space in the heater. This valve u may be manipulatedmanually, but the invention contemplates its movement in response to athermostat, shown at tit, in duit a from the heater iii. The thermostatI is oi the type which contains a fluid which expands under an increasein temperature and this expanding fluid is conducted through a pipe 36to a bellows s'i carried by an arm 38 on the exterior of duct 86. Theupper movable end of bellows 31 is pivoted to an arm 39 which isconnected to the valve shaft of the butterfly valve as.

During operation, the thermostat 38 will serve to maintain a constanttemperature of the escaping carbon dioxide vapor because if it becomestoo hot, the thermostat 35 will operate to close the valve as and reducethe amount of fuel supplied to the heater. If, on the other hand, thetemperature of the escaping vapor from heater is drops too low, thethermostat as will function to open the valve is and cause a greatercombustion within the chamber of heater it.

In the modification shown in Figure 3, the carbon dioxide is heatedwithin the heater before it reaches the nozzle. In this embodiment, theheater includes a shell Mi, the interior wall of which is insulated inthe same manner that shell is is internally insulated. This shell to,however, is formed with a lateral extension ti which serves as a flueportion and which terminates in a Venturi portion as. The nozzle 83 isdirected into the Venturi t2 and the conduit from the supply tank tothis nozzle is coiled within the interior of the heater, as shown at Mand it. The coils to are subiected to the direct flame of the burnngfuel and the coils to are exposed to the combustion gases by beinglocated in the flue portion ii of the shell til.

As the incoming carbon dioxide initially passes through the coils as inthe flue portion ll of shell 80, and as this carbondloxide is cold, itwill cool the combustion gases and cause condensation of the moisturewhich is in the combustion gas'as a product of combustion. This moisturecondensed from the combustion gases drops to the lower part of theextension ii of the heater shell, where it collects and is conducteddownwardly through a pipe 68 to a valve controlled trap. M.

The moisture which is i'ormed as a product of combust on is thereforeremoved from the gases before they enter the Venturi 42 for delivery tothe d scharge end 01' the conduit 8. This is of importance because thisremoves moisture from the system which would tend to elevate the dewpoint of the air w thin the room 9. In passing through the coils M. thecarbon diox de is heated by conduct on of heat through the coil walls.

The heater shown in Figure 3 is sup lied w th fuel in the same mannerthat the heater of F gure 2 is sup lied. Th s includes the duct 48 whichextends upwardly into the combust on space and wh ch corresponds to theduct 2! in Figure 2.

Figure 4 shows a d fferent type of device for supplying a combustiblemixture to the combustion space. The duct 50 there shown correthe outletportion of consponds to either the duct 2i 0! Figure 2, or the duct I!of Figure 3, since this charge iorming device may be used with eitherheater. To the lower end of duct 50 is attached a duct 5| which is ofT-tormatlon so that it has the inlet portions 52 and 53. The branch ductor is intended to deliver air to the upwardly rising duct 5i and a disc54 interposed therein has an orifice therethrough of a size to determinethe amount of air which will be supplied. The branch duct 53 is intendedto be connected to a source of gaseous fuel, as for example, ordinaryilluminating gas. Interposed in branch at is a disc be having an orificetherethrough of a size to determine the volume of flowing gas. A gassupply line be is connected to the branch duct 58 through a pressurereducing valve o'i which preferably atmospheric pressure.

By appropriately regulating the pressure reducing valve ti and employingdiscs tit and as having the proper sized orifices therethrough, amixture of the correct proportions for combustion will be suppliedupwardly through the ducts be and Bi for delivery into the combustionspace. The voiurne of this mixture which is supplied will be limited bya valve at corresponding to valve 321 and preferably operated by abellows as under thermostat control, as has been described. If desired,the heater may be a built-in part of the fire truck so that it need notbe positioned apart from the truck when it is to be put in use as shownin Figure 1. In the case of a nonmobile fire extinguishing equipment,the heater may, in similar manner, be either movable as shown, or fixedin position. In operation, the valve ii is first turned on so as tocreate a suction todraw fuel into the combustion space of the heater andthen the fuel mixture in this space is ignited.

What I claim is:

1. Apparatus for extinguishing fires comprisa container for storingliquid carbon dioxide, a conduit for conducting the carbon dioxide fromthe container to a place of use, means providing a closed combustionspace, and means for deliverin fuel to said space for combustiontherein, said conduit having a portion thereof passing through saidcombustion space and including an aspirator jet within the combustionspace to draw the products of combustion into the conduit to elevate thetemperature of the flowing carbon dioxide.

2. Apparatus for extinguishing fires comprising a container for storingliquid carbon dioxide, a conduit for conducting the carbon dioxide fromthe container to a place of use, a shell having thermally insulatedwalls, means for delivering fuel to the lower part of the shell forcombustion therein. said conduit having a portion thereof passingthrough the upper part of the combustion space and including anaspirator jet within the combustion space to draw the products ofcombustion into the conduit to elevate the temperature of the flowingcarbon dioxide.

3. Apparatus for extinguishing fires comprising a container for storingliquid carbon dioxide. a conduit for conducting the carbon dioxide fromthe container to a place of use, a shell having thermally insulatedwalls, means for delivering fuel to the lower part of the shell forcombustion therein, said conduit having a portion thereof passingthrough the upper part of the combustion space and including anaspirator jet within the combustion space to. draw the products ofcombustion into the conduit to elevate the temperature of the flowingcarbon dioxide, said fuel delivreduces the gas to ering means beingsubjected to atmospheric pressure whereby the aspirator jet serves todraw the fuel into the shell.

4. Apparatus for extinguishing tires comprising a container for storingliquid carbon dioxide, a conduit for conducting the carbcn dioxide fromthe container to a place of use, a shell having thermally insulatedwalls, and providing a combustion space therein a duct entering intosaid combustion space and having connected to its exterior an air andfuei'mixing device, said conduit having a portion thereoi' passingthrough the combustion space and including an aspirator jet within thecombustion space to draw the products of combustion into the conduit toelevate the temperature oi the flowing carbon dioxide, said aspiratorJet also serving to draw said mixture irom said device and into thecombustion chamber.

5. Apparatus for extinguishin fires comprising a container for storingliquid carbon dioxide, a conduit for conducting the carbon dioxide fromthe container to a place of use, means providing a closed combustionspace, a duct entering into said combustion space for the delivery offuel to said space for combustion therein, said conduit having a portionthereof passing through the combustion space and including an aspiratorjet within the combustion space to draw the products of combustion intothe conduit to elevate the temperature of the flowingv carbon dioxide,said aspiextending into the interior of said shell, means ior deliverina combustible iuel to said duct for combustion inside the shell, and avalve in said duct tor regulating the rate of flow 01 fuel through theduct.

9. A heater for elevating the temperature or carbon dioxide beingdelivered through a conduit @rom a carbon dioxide container to a placeof use, said heater comprising a shell having insulated walls, anaspirator jet therein including an inlet nozzle and an outlet Venturlfor connection into the conduit with the nozzle disposed to receivecarbon dioxide from the container, a duct extending into the interior orsaid shell, means for delivering a combustible fuel to said duct forcombustion inside the shell, a valve in said duct, and

rator Jet also serving to draw i'uel through said duct into said space,and a valve in said duct to regulate the flow oi iuelto said combustionspace.

6. Apparatus for extinguishing fires comprising a container for storingliquid carbon dioxide, a conduit for conducting the carbon dioxide fromthe container to a place of use, means providing a closed combustionspace, a duct entering into said combustion space for the delivery offuel to said space for. combustion therein, said conduit having aportion thereof passing through the combustion space and includin anasplrator iet within the combustion space to draw the products ofcombustion into the conduit to elevate the tem..

perature of the flowing carbon dioxide, said aspiratcr jet also servingto draw fuel through said duct into said space, a valve in said duct toregulate the flow oi fuel to said space, and a thermostat in the outletof said conduit from the heater and having an operative connection tosaid valve.

7. A heater for elevating the temperature of carbon dioxide beingdelivered through a conduit from a carbon dioxide container to a placeoi use, said. heater comprising a shell having insulated walls, anaspirator jet therein including an inlet nozzle and an outlet Venturifor connection into the conduit with the nozzle disposed to receivecarbon dioxide irom the container, a duct extending into the interior ofsaid shell, and means for delivering a combustible iuel to said duct forcombustion inside the shell.

8. A heater for elevating the temperature of carbon dioxide beingdelivered through a conduit from a carbon dioxide container to a placeof use, said heater comprising a shell having insu. lated walls, anaspirator Jet therein including an inlet nozzle and an outletVenturli'or connection into the conduit with the nozzle disposed toreceive carbon dioxide from the container, a duct a thermostat exposedto the delivery through the Venturi and having a connection to the valveto control its position.

10. A heater for elevating the temperature of carbon dioxide beingdelivered through a conduit from a carbon dioxide container to a placeof use, said heater comprising a shell having insulated walls, anaspirator Jet in communication with the interiors! the shell andincluding an inlet nozzle and an outlet Venturi, a pipe within saidshell and connected at one end to-said nozzle, the other end of the pipebeing connectable to receive carbon dioxide from the container and theVenturl being connectlble to deliver the carbon dioxide to the place ofuse, a duct extending into the interior of saidshell ztcr delivering acombustible fuel to the interior of the shell, the entrance portion orsaid pipe being disposed out of the flame area from the duct but in thepath oi the combustion gases to cause condensation of the moisture insaid gases, and means for removing the condensed moisture from theshell.

11. A heater dor elevating the temperature oi. carbon dioxide beingdelivered through a conduit from a carbon dioxide container to a placeoi use, said heater comprising a shell having insulated walls, anaspirator jet in communication with the interior of the shell andincluding an inlet nozzle and an outlet Venturi, a pipe within saidshell and connected at one end to said nozzle, the other end of the pipebeing connectavble to receive carbon F Number dioxide from the containerand the Venturi being connectible to deliver the carbon dioxide to theplace of use, a duct extending into the interior of said shell fordelivering a combustible fuel to the interior of the shell, the entranceportion 0d! said pipe being disposed out of the flame area from the ductbut in the path of the combustion gases to cause condensation of themoisture in said gases, and a liquid trap to receive the condensedmoisture and remove it from the shell.

HILDING V. WILLIAMSON.

I file of this patent:

UNITED STATES PATENTS Name Date Connelly "Dec. 7, 1875 Rew June 25, 1389Weidig Sept, 12, 1893 Osborne Oct. 15, 1908

